At present, with the rapid development of communications technologies, users have increasingly high requirements on efficiency of network resource utilization, and subsequently, a cluster system emerges.
There are multiple nodes in a cluster system, where only some of the nodes can be presented to the outside, and the nodes presented to the outside are referred to as edge nodes. If multiple edge nodes all support Multi-Protocol Label Switching (MPLS) traffic engineering (TE), a TE topology among these nodes can be presented by using TE links between the nodes.
When data that is transmitted from a node outside the cluster system needs to be forwarded to a next node through the cluster system, a controller in the cluster system calculates, according to information carried in the data, a transmission path that can provide a service, so that the data can be transmitted to the next node through the cluster system. Therefore, a maximum bandwidth that can be provided by the cluster system needs to be released to another node outside the cluster system, so that a bearer capability of the cluster system when the cluster system bears data is released to the another node outside the cluster system.
In the prior art, the maximum bandwidth that can be provided by the cluster system is obtained by simply adding bandwidths of all transmission links that are in the cluster system and are directly connected to the edge nodes. Refer to FIG. 1, which is a schematic diagram for obtaining a maximum bandwidth of a cluster system in the prior art. As shown in FIG. 1, in the cluster system, bandwidths of transmission links that are directly connected to an edge node A2 add up to 50 G; therefore, the maximum bandwidth that can be provided by the cluster system is 50 G, and a bandwidth that is needed for data transmission between a node A1 and the edge node A2 cannot be greater than 50 G. This method for calculating the maximum bandwidth of the cluster system has low accuracy, and if the maximum bandwidth obtained in this manner is announced to a node outside the cluster system, it may cause that the cluster system cannot transmit data when a bandwidth needed by the data to be transmitted exceeds a bearer capability of the cluster system.